Vauxhall Corsa 1.7d?

After recent track rod end replacements, my car veered to the left. thinking this was a wheel alignment problem I immediately had this checked/calibrated, and found that the problem had eased somewhat. However I also notice that the service light comes on and I lose my speedometer reading until I surpass 40mph, when the light goes out the speedometer behaves correctly and the steeering becomes not only firmer but true.